SPH 3UO LESSON PLANS


Unit 5: Electricity and Magnetism
- Electrical concepts
- Magnetic field concepts
- Electromagnetism
- Electromagnetic induction
- Motor principle
- Generators
Text: Physics 11
(Addison-Wesley)
 
 
Lesson One
Summary:
 -electric charge(nature, coulomb)
-Coulomb’s law(force)
-electric current(conventions, measuring)
-view video (Bill Nye)
 Practice:
-do p. 454, #1,2
-do p. 457, #1,2
Review:
-do p. 459, #1-10
Assignment:
-do challenge, p. 456

CURRENT

Current
-charge is measured in coulombs(C)
-1C =  6.24 x 1018 elementary charges (protons or electrons)
-the magnitude of the charge on a proton or an electron is 1.6 x 10-19C
The quantity of charge on an object is given by Q=Ne
ex. while rubbing your feet on a carpet you pick up a charge of -5 mC. How many excess electrons do you have?

Electric current is the amount of charge passing a certain point in a wire every second.
I=Q/ /\t
-if one amp flows through a wire that means every second 1 C of charge (or 6.24 x 1018 electrons) passes every point in the wire
-An ammeter is used to measure the current

Lesson Two
Summary:
 -electric potential difference
-measuring potential difference
-conditions for current flow
-circuit schematic diagrams
-view video (PEEL)
 Practice:
 -do p. 463, #1,2
-do p. 464, #1,2
Review:
 -do p. 468, #1-11
Assignment:
-do challenge, p.461

ELECTRIC POTENTIAL

Electric Potential
...commonly called voltage, it is a measure of how much energy the electrons have and can be calculated by:
V= W/Q

A voltmeter is used to measure the voltage
Learn symbols for light bulb, resistor, switch, ammeter, voltmeter, cell, battery, variable voltage source, wires crossing, wires joined

Series and Parallel Circuits...in a series circuit, current can flow in one path only.
...in a parallel circuit current can flow along two or more paths
Lesson Three
Summary:
 -Kirchhoff’s current law
-Kirchhoff’s voltage law
-series-parallel combinations
 
Practice:
 -do p. 473, #1,2
-do p. 474
 -do p. 476
Review:
 -do p. 477, #1-10
Assignment:
-do challenge, p.470
-do challenge, p.471
-do challenge, p.472
Due:
-p. 477, #9,10 next class

CONSERVATION OF ENERGY

Kirchoff's current law:
At any junction in an electric circuit, the total current flowing into the junction is equal to the total current flowing out of the junciton.

Kichoff's voltage law:
The sum of the voltages around any closed path is equal to zero.

Lesson Four
Summary:
 -do p. 479, lab 1
-do p. 480, lab 2
 Assignment:
-do p. 479, lab 1
-do p. 480, lab 2
Due:
-p. 479, lab 1 next class
-p. 480, lab 2 next class

ELECTRICITY LABS

Lesson Five
Summary:
-resistance
(ohm’s law, unit, resistors,
superconductors)
-do p. 513, lab 1
 Practice:
 -do p. 493 #1,2
Review:
 -do p. 494 #1-10
Assignment:
-do challenge, p.488
-do p. 513, lab 1

RESISTANCE

Ohm's  Law:
Resistance is the property of a material that impedes the flow of current
Ohm's Law states that the voltage across a conductor is directly proportional to the current flowing through it.
If a graph of V vs. I gives a straight line then the material is said to be Ohmic
Resistance is the slope of the line...R = V/I
Since it is a straight line the slope, and therefore the resistance, is constant
Non-ohmic conductors hava a curved graph
Resistance is still the slope of the graph and R= V/I but resistance is not constant.
Risistance is measured in V/A of ohms

Factors Affecting Reistance
1) Length...the more material the current has to flow through the more resistance
R is directly proportional to L
2) Cross-sectional Area...the wider the wire is the less resistance there is
R is directly proportional to 1/A
3) Temperature...as the temperature increases so does the resistance
4) Type of material...see table 13.2, page 490

Superconductors:
-are materials that have zero resistance
-they do not exist at room temperature
-the hottest superconductors exist at 77 K
Lesson Six
Summary:
 -resistors in series/parallel circuits 
-series-parallel combinations
 Practice:
 -do p. 501 #1,2
-do p. 504 #1
Review:
 -do p. 504 #1-11
Assignment:
-do challenge, p.496
-do challenge, p.497
-do challenge, p.499
-do challenge, p.500
Due:
-p. 504 #1-11 this class

RESISTORS

Resistors in Series and Parallel
Resistors in series can be replaced by one resistor by the formula:
Rt = R1 + R2  + R3 +...+  Rn   ....
Resistors in parallel can be replaced by one resistor by the formula:
1/Rt = 1/R1 + 1/R2  +1/R3 +...+  1/Rn   ....

Series and Parallel Combinations
Most circuits contain both parallel and series combinations
These must be done in simple steps...
1) draw a box around any resistors in series and calculated the equivalent resistance
2) Draw a box around any resistors in parallel and calculated the equivalent resistance
3) Draw a new diagram with the equivalent resistances
4) Repeat steps 1-3 until there is only on resistor in the diagram


Lesson Seven
Summary:
 -do p. 514, lab 2
-work on circuit problems
-complete labs
 Assignment:
-do p. 514, lab 2

CIRCUITS


Lesson Eight
Summary:
 -electric power
-electric energy
-do case study, p.511
-cost of energy worksheet
 Practice:
 -do p. 509 #1,2
-do p. 510 #1,2
Review:
 -do p. 512 #1-13
Assignment:
-do challenge, p.506
-do challenge, p.507
-do challenge, p.508,1-3
-do case study, p.511
-cost of energy worksheet
Due:
-cost of energy worksheet next class

ELECTRIC POWER

Electric Power
Recall... P = E / /\t
For electricity this turns into P = IV
Units for Power = ampere volt = watt
Since V= IR; P = I2R
Since I = V/R; P = V2/R


Lesson Nine
Summary:
 -magnetism
(poles, fields, force)
-view video (Bill Nye, PEEL)
-do discovery, p.519
-do discovery, p.522
 Review:
 -do p. 524 #1-7
-do p. 524 #1-7
Assignment:
-do discovery, p.519
-do discovery, p.522

MAGNETISM
-note the discoveries in this section can be done after covering all topics
Lesson Ten
Summary:
 -current and magnetic field
(right hand rules)
-electromagnet
-view video (PEEL)
 Practice:
 -do p. 529 #1,2
Review:
 -do p. 530 #1-12

CURRENT AND MAGNETIC FIELD

Lesson Eleven
Summary:
 -ferromagnetism
-use of electromagnetism
-do discovery, p.532
-introduce project, p.579
 Review:
 -do p. 534 #1-6
-do p. 536 #1-6
Assignment:
-do discovery, p.532
-do project, p.579

FERROMAGNETISM

Lesson Twelve
Summary:
 -motor principle
-right had rule
-DC motors
-uses
-do discovery, p.548
 Practice:
 -do p. 547 #1,2
-do p. 551 #1,2
-do p. 552 #1,2
Review:
 -do p. 552 #1-9
-do p. 555 #1-4
-do p. 558 #1-6
Assignment:
-do challenge, p.557
-do discovery, p.548

MOTOR PRINCIPLE


Lesson Thirteen
Summary:
 -electromagnetic induction
-lenz’s Law
-view video (PEEL)
-do discovery, p.560
-do discovery, eddy current apparatus
-do discovery, p.565
 Practice:
 -do p. 561 #1,2
-do p. 562 #1,2
Review:
 -do p. 567 #1-10
Assignment:
-do discovery, p.560
-do discovery, eddy current apparatus
-do discovery, p.565

ELECTROMAGNETIC INDUCTION